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BUG: KCSAN: data-race in __nf_conntrack_alloc / __nf_conntrack_find_get

write to 0xffff888023621b08 of 4 bytes by interrupt on cpu 1:
 __nf_conntrack_alloc+0x147/0x270 net/netfilter/nf_conntrack_core.c:1508
 init_conntrack+0x178/0xa90 net/netfilter/nf_conntrack_core.c:1576
 resolve_normal_ct net/netfilter/nf_conntrack_core.c:1674 [inline]
 nf_conntrack_in+0x37f/0xad4 net/netfilter/nf_conntrack_core.c:1829
 ipv4_conntrack_in+0x19/0x20 net/netfilter/nf_conntrack_proto.c:178
 nf_hook_entry_hookfn include/linux/netfilter.h:136 [inline]
 nf_hook_slow net/netfilter/core.c:589 [inline]
 nf_hook_slow_list+0x133/0x340 net/netfilter/core.c:627
 NF_HOOK_LIST include/linux/netfilter.h:337 [inline]
 ip_sublist_rcv+0x56f/0x590 net/ipv4/ip_input.c:606
 ip_list_rcv+0x262/0x290 net/ipv4/ip_input.c:643
 __netif_receive_skb_list_ptype net/core/dev.c:5354 [inline]
 __netif_receive_skb_list_core+0x34b/0x450 net/core/dev.c:5402
 __netif_receive_skb_list+0x262/0x2e0 net/core/dev.c:5454
 netif_receive_skb_list_internal+0xda/0x330 net/core/dev.c:5564
 gro_normal_list net/core/dev.c:5718 [inline]
 napi_complete_done+0x1b2/0x420 net/core/dev.c:6443
 wg_packet_rx_poll+0x1208/0x1290 drivers/net/wireguard/receive.c:496
 napi_poll+0x178/0x4c0 net/core/dev.c:6759
 net_rx_action+0x17a/0x480 net/core/dev.c:6829
 __do_softirq+0x12c/0x2b1 kernel/softirq.c:298
 asm_call_irq_on_stack+0xf/0x20
 __run_on_irqstack arch/x86/include/asm/irq_stack.h:26 [inline]
 run_on_irqstack_cond arch/x86/include/asm/irq_stack.h:77 [inline]
 do_softirq_own_stack+0x32/0x40 arch/x86/kernel/irq_64.c:77
 do_softirq kernel/softirq.c:343 [inline]
 __local_bh_enable_ip+0xba/0xd0 kernel/softirq.c:195
 __raw_spin_unlock_bh include/linux/spinlock_api_smp.h:176 [inline]
 _raw_spin_unlock_bh+0x33/0x40 kernel/locking/spinlock.c:207
 spin_unlock_bh include/linux/spinlock.h:399 [inline]
 ptr_ring_consume_bh include/linux/ptr_ring.h:367 [inline]
 wg_packet_decrypt_worker+0x18c/0x730 drivers/net/wireguard/receive.c:507
 process_one_work+0x3e1/0x950 kernel/workqueue.c:2272
 worker_thread+0x635/0xb90 kernel/workqueue.c:2418
 kthread+0x1fd/0x220 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296

read to 0xffff888023621b08 of 4 bytes by task 16779 on cpu 0:
 nf_ct_is_expired include/net/netfilter/nf_conntrack.h:272 [inline]
 ____nf_conntrack_find net/netfilter/nf_conntrack_core.c:747 [inline]
 __nf_conntrack_find_get+0x1c7/0xac0 net/netfilter/nf_conntrack_core.c:778
 resolve_normal_ct net/netfilter/nf_conntrack_core.c:1672 [inline]
 nf_conntrack_in+0x31e/0xad4 net/netfilter/nf_conntrack_core.c:1829
 ipv4_conntrack_local+0xc2/0x120 net/netfilter/nf_conntrack_proto.c:200
 nf_hook_entry_hookfn include/linux/netfilter.h:136 [inline]
 nf_hook_slow+0x72/0x170 net/netfilter/core.c:589
 nf_hook include/linux/netfilter.h:256 [inline]
 __ip_local_out+0x282/0x2a0 net/ipv4/ip_output.c:115
 ip_local_out+0x22/0x80 net/ipv4/ip_output.c:124
 iptunnel_xmit+0x31a/0x460 net/ipv4/ip_tunnel_core.c:82
 ip_tunnel_xmit+0x1084/0x11b0 net/ipv4/ip_tunnel.c:807
 __gre_xmit net/ipv4/ip_gre.c:466 [inline]
 ipgre_xmit+0x4d9/0x530 net/ipv4/ip_gre.c:648
 __netdev_start_xmit include/linux/netdevice.h:4735 [inline]
 netdev_start_xmit include/linux/netdevice.h:4749 [inline]
 xmit_one+0xf9/0x2e0 net/core/dev.c:3564
 dev_hard_start_xmit net/core/dev.c:3580 [inline]
 __dev_queue_xmit+0xeef/0x1510 net/core/dev.c:4140
 dev_queue_xmit+0x13/0x20 net/core/dev.c:4173
 __bpf_tx_skb net/core/filter.c:2116 [inline]
 __bpf_redirect_no_mac net/core/filter.c:2141 [inline]
 __bpf_redirect+0x544/0x750 net/core/filter.c:2164
 ____bpf_clone_redirect net/core/filter.c:2448 [inline]
 bpf_clone_redirect+0x168/0x1c0 net/core/filter.c:2420
 bpf_prog_801cabf80fc815cd+0x59/0x68
 bpf_dispatcher_nop_func include/linux/bpf.h:644 [inline]
 bpf_test_run+0x266/0x450 net/bpf/test_run.c:50
 bpf_prog_test_run_skb+0x6f0/0xe70 net/bpf/test_run.c:581
 bpf_prog_test_run kernel/bpf/syscall.c:3125 [inline]
 __do_sys_bpf+0x39d6/0x9aa0 kernel/bpf/syscall.c:4417
 __se_sys_bpf kernel/bpf/syscall.c:4357 [inline]
 __x64_sys_bpf+0x3d/0x50 kernel/bpf/syscall.c:4357
 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 16779 Comm: syz-executor.1 Not tainted 5.10.0-rc6-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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